Heater



FIG. 1 is a perspective view of the heater showing my new design;

FIG. 2 is a front view of the device illustrated in FIG. 1;

FIG. 3 is an rear view thereof;

FIG. 4 is a first side view thereof;

FIG. 5 is a second side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines showing an electrical plug are for the purpose of illustrating the environment in which the heater is used, and forms no part of the claimed design. 

CLAIM The ornamental design for heater, as shown and described. 